Drive for engine starters



w 0 wa, f 3 nw 9 wz: x. w, J

Zara/'ice c RINGWALD DRIVE FOR ENGINE STRTERS Filed oct. 24. 1924 Aug. 24 1926.

Patented Aug. 24,

UNITED `STfA'Ts .oLAnnNon muGwALn,

Dmvn Fon innemu s'mn'rnns.

" Apumion fil'za October 24, '1924. serial m. 745,555.

invention relates to drives for engine starters. I am aware that heretofore it has been the practice in starting internal .combustion engines to employ. a threaded lsleeve mounted upon the motor shaft and connected to said motor shaft by a spring'connection. An internally threaded .drive rpi'nion forms a nut for said threif ded sleeve and it is moved axially into 'mesh withthe ring gear on the fly wheel of the engine. by rotation of the motor shaft and its threaded sleeve, and after the nut or pinion is meshed With' wheel and l.thus crank the engine. v

In such devices, the parts must fit loosely and move easily, because vthe pinion nut is said ring gear', it is rotated to turn the fiy held by inertia While it'moves axially into,

mesh withthe ring Gear. -Since the sleeve is interposed between the -pinion and the shaft, there is excessive play and lostf motion ,with consequent friction in the gear teeth and inaccuracy in fit of 'the parts.V The interposition of the sleeve also demands a pinion of larger diameter with consequently, less leverage.

According lto my invention, 'I' make the parts fewer in number by having the pinion provided with` an axially extending sleeve which sleeve and pinion are unitary and fit uponthe motor shaft. An external nut connected through `a spring connection with the motor shaft then servesto thread the pin-` ion and its sleeve into. meshwith .the ring gear on the fiy wheel and thus secure meshmg between the drivingpinion and the ring gear.

By' the employment of my invention, it is possible to use a pinion of smaller diameter with a consequent increasein starter ratio. The use of my invention .gives greater in-` ertia to the `pinion :Without the addition of extra material for ;that purpose. The pinion,.furthermore,is now mounted upon the ground motor shaft with a fine fit, thereby securing accurate centering and better support, not only from the motor shaft, but also y from the bearings of the motor. Also there is less pounding and tilting of the pinion..y

Furthermore, the construction permits the pnion to be driven closer to the bearing of the starter motor, so that'longer life and better weari'ng qualities are assured. Above all, the construction is cheaper than any heretofore proposed with which I am familiar.` I

or onIcAeo, ILLmoIs, AssIcNon vor ONE-:mur 'ro JOHN A.

nmunnn, or EvaNs'roN, Innmoxs.

Inorder to acquaint those skilled in the art with the manne'r of constructing and operating my invention,' I 'shall nowdescribe a specific embodimentvof the same in connection with the accompanying drawmg, in. which: v o. Figure 1 is a side elevational view of a' device embodying my invention;

Fig. 2 is a Vertical longitudinal sectional view through the same;

Fig. 3 is a transverse section taken on the line 3-3 of Fi'g. 2; and

Fig. 4 is a similar transverse section taken on the line 4-4 of Fig. 2.

The bearin'g llof the driving motor supports the motor shaft 2, this motor shaft having a `shoulder 3 and a reduced portion .4 extending therefrom, 'this reduced portion being carefully ground to fit the interior of the pinion and sleeve 'member 5 which fits upon said shaft 4. The pinion and sleeve member 5is a unitary membercomprising a pinion 6 and a threaded portion 7 extending toythe rear of the same. Upon the rear end of the threaded sleeve 7'I provide an| unbalanced stop nut 8 which is securely fastened upon the rear end of the threaded part 7 to: provide a stop in'conjunction with the driving nut 9 when the :two parts'are engaged. This stop nut 8 is eccentric and is preferably threaded upon the end of the threadedv sleeve 7 b screw threads of fine pitch inclined in a ire'otion such as to pro'- duce tightening -of 'the nut 8 thereupon when it engages the nut 9. The threaded sleeve 7 has screw threads of coarse pitch and preferablyl of multiple thread.

The nut 9 is connected to the end ofa suitable spring 10, the end of the spring being formed into a loop or eye at 11 and the machine screw 12 passing radially through said eye 11 and into the nut9 and being held 'against rotatipn by a suitable bendable lock washerv 13.

At *ze outer end of'the motor shaft 4, Ii

.being passed into the body of'vthe collar 14 no' a and engaging the end of the shaft 4. The

'connecting said collar 14 and the 'end of vthe shaft 4.

A pair of sheet metal sleevemembers 17 and 18 are passed under the ends of the spring'lO on the collar I14 and the nut 9, re-

spectively, these sheet metal slceves serving to exclude foreign matter from the threads' of. the sleeve 7, and serving also as a support for the convolutions of the helical spring 10, and as a container for lubricant.

The pinion 6 and shaft 4 are mounted closely adjacent the ring gear 21.-onthe fly Wheel 22 'of the motor, the parts being so designed as to permit the pinion 6 to run axia ly up to theshoulder 3 or closely 'adjacent thereto, when the stop nut 8 engages the end' of the dniving nut 9.

The operation of the device is as'follows: The shaft. 4 being set closely adjacent the ring gear 21 and in proper endwise ad- ]'ustment, rotation of the motor shaft 2 in a counter clockwise direction as'viewed from 'the right of F igs. 1 and 2 results in a movement of the connected parts, namely,vthe collar 14, bolt 16, spring 10, bolt 12, and drivingonut 9. The inertia of the 'pinion and sleeve member 5, together With the eccentrio nut 8, tends to hold these parts, against rotation While the vnut 9 is rotated to advance the pinion 6 axially, until it Strikes the teeth of the ring gear 21 and meshes With the same, whereupon engagement of the stop collar 8 with the end of the driving nut 9, re`sults in rotation of the pinion 6 and consequent driving of the ring gear 21 to crank the engine. Upon starting of the engine in the same direction at a speed greater than the speed of the nut, the member '5 comprising the pinion 6 and the threaded sleeve 7, Will be carried back axially to the left, as in'dicated in-Figs. 1 and 2. It Will be obvious'that, if -desired, a collar may be pro-' vided at the left end of thepinion 6 asl shown in Figs. 1 and 2, or that if desired the pinion 6 may be run up against the shoulder 3 'on the shaft 2. On the return motion the pinion stops by engaging the outer face of collar 9. i

From the foregoing, it Will be seen that I have 'provided a construction which permits of a pinion of a minimum number of teeth and ofa minimum diametenin order to secure a maximum starting ratio.- At the same, time, the rearwardly extending thread- 'ed .sleeve 7, gives the pinion 6 greater inertia without 'increasing the diameter of the same and thus makes for-certainty of operation. The pinion 6 is held accurately and with much greater bearing on I the ground shaft section 4 than has been,V shaft 4 is keyed to said collar 14 inaddition possible in devices of the prior'art. It will to the engagement of thebolt 16 forrigidly be noted that the pinion can now be brought up' to the motor bearings, since no collar is 'required at the inneriend of the pinion as in devices of theprior art, and better support is thereby gained. In addition to the above advantages, the construction is less expensive and involves a less number of parts.

I claim: g .1. In combination, a sleeve member bearing a coarse external thread and having a pinion on one end, a threaded collar on said threaded partof the sleeve member, an attaching collar, a helical. drive spring conuentric withisaid sleeve between said two collars and a stop on the threaded end of the sleeve for engaging the thr aded collar to stop the forward moveme'nt of the member.

2. lIn combination, a drivingshaft, an" externally threaded sleeve on said shaft having anintegral pinion at one-end, an internally threaded collarV embracing the threads on` said sleeve, a stop collaron the end of the sleeve opposite 'said pinion, a collar nonrotatably secured to said driving shaft, ad a helical spring .connectingsaid last named collar and said internally' threaded collar' and extending over the endof said sleeve and its attached stop collar.

3.1111 combination, a rotatable motor' shaft,v a one-piece sleeve'and pinion member mount- :ed directly on said shaft, a threaded nt embracing the sleeve, a collar on the end of the motor shaft and a coil spring between said collar and said' nut sleeve.. p i 4. In combination, a one-piece sleeve and pinion member adapted to be `mounted on a. driving shaft, a threaded nut onsaid sleeve, said sleeve. having a threaded portion with a shoulder at the rear end of the threaded por- -tio n, an attaching collar mounted on and secured to the motor shaft, and a helical connectingspring between the collar and the nut. i

' 5. In combination, a motor shaft adapted to be closely positioned adjacent a ring gear for an internal combustion engine, a threaded sleeve and pinion member mounte'd directly on saidfshaft, said pinion forming a shoulder at one end of the threaded sleeve and a stop collar mounted at the other end of the threaded sleeve and forming a shoulder, a threaded nutbetween said Shoulders on sa'id threaded sleeve, a collar secured on the-outer end ofthe motor shaft and a coil spring connecting said collar With said threaded nut and embracing'the sleeve.

In Witness-whereof, I hereunto. Subscribe my name this-21 day of October, 1924.

" CLARENCEv RINGWALD; 

